A small, concentrated downburst affecting an area less than 4 kilometers (about 2.5 miles) across. Most microbursts are rather short-lived (5 minutes or so), but on rare occasions they have been known to last up to 6 times that long.

A COMPREHENSIVE GLOSSARY OF WEATHER

A small, concentrated downburst affecting an area less than 4 kilometers (about 2.5 miles) across. Most microbursts are rather short-lived (5 minutes or so), but on rare occasions they have been known to last up to 6 times that long.

A microburst is a small-scale downburst, thus a very localized column of sinking air caused by a small and intense downdraft (the air does not spin like it does in the case of a cyclone or tornado) within a thunderstorm. There are two types of microbursts: wet microbursts and dry microbursts. They go through three stages in their life cycle: the downburst, outburst, and cushion stages. The scale and suddenness of a microburst makes it a great danger to aircraft due to the low-level wind shear caused by its gust front, with several fatal crashes having been attributed to the phenomenon over the past several decades.